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To develop a hydrogel sensor system using the Hall effect to detect the degree of swelling, gels containing high concentrations of magnetic particles are necessary to induce a strong magnetic field. For this purpose, hydrogels based on poly(N-isopropylacrylamide) cross-linked with Laponite XLS are modified with various magnetic nanoparticles. The focus of this work is to introduce high particle densities with a homogeneous distribution into the gel. Particles are coated with 3-(trimethoxysilyl)propyl methacrylate to bind them into the network structure. The swelling behavior and temperature response of gels containing pure and modified particles are compared to the unmodified clay gel. Ferrogels are further synthesized in a magnetic field to permanently align magnetic nanoparticles in the network. This results in permanently embedded rod-like structures spanning the entire length of the gel. The influence of this anisotropic distribution on the mechanical properties of the hydrogel is investigated through compression measurements.

Environmentally adaptable grease (EAG) lubricants are essential in applications with loss lubrication due to their biodegradable nature. This is because the lubricants could be expelled into the environment during usage in some applications e.g., marine and mining applications. However, although this type of grease is sustainable to use, it also needs to bridge the performance gap it has with the mineral-based grease counterpart.  In this thesis project, a tribological evaluation comparison between the performance of EAGs and traditional mineral-based greases in large open gears is carried out. A twin disc tribometer is used to mimic the contact mechanisms of the test gears while being lubricated automatically by the grease samples through a syringe pump. For the experiments, the material surface of all the discs in the tribometer setup is steel while the different grease samples are tested for each setup. Two of the grease samples; UPL 04123 (NLGI 1.5) and UPL 04124 (NLGI 0.5) are fully formulated EAGs, while the third is a popular commercial mineral-based grease currently used in large open gears in the mining industry. An investigation of the wear of the discs used in each grease test is carried out using optical interferometry and a Scanning electron microscope (SEM). The wear volumes and wear rates are then analysed and compared to evaluate the performance of the grease samples. The wear results from the tribological characterisation using the twin disc are validated with the ISO 14635-3 standard on the FZG back-to-back test rig. Also, chemical characterisation of the unused and used grease is carried out using the advanced ATR-FTIR method to evaluate additive depletion and lastly an SEM-EDS analysis to confirm the presence of tribofilm on the surfaces of the disc samples. In conclusion, it is found that there is a correlation between the consistency of the grease sample and wear prevention; where the commercial grease with the least consistency performs best, followed by the 0.5G and lastly the 1.5G. Also, there are clear indications in the wear rates of the actions of extreme pressure additives activation at high contact pressures between the discs. The inadequacies of the ATR-FTIR and SEM-EDS methods to evaluate additives and tribofilm respectively are also discussed.

Optical scattering measurement devices are used to measure light reflection and light scattering from materials, to obtain data of the surface and bulk properties of materials. The measurement data are often used in research and development projects where material requirements are important, also for quality control in manufacturing processes, in different optical simulations and can be used for photorealistic rendering. In this master thesis project conducted at AFRY, a multifunctional team will develop an optical scattering measurement device that aims to collect data more accurately than current devices on the market. This thesis will focus on the mechanical design of the device which consists of the stability and movement of the components, the environment of the measurements and material selection with a focus on performance and sustainability. The optical model that will act as a basis for the development will be a gonioreflectometer consisting of a material sample, sample holder, light source, detector and an environment in which the measurements are conducted. Some of the physical, cognitive and emotional needs of the intended user are efficient use, low risk of misuse, reliable and high precision. A thorough requirement specification was made as a framework for the concept generation. The selected concept provides the movement of the optical components with an angular step enabling the desired optical scattering measurement. The selected stepper motor and gear ratio provides the flexibility of the movement, making it easy for the user to change angular steps of the optical components, enabling both fine and rough measurements. A separating screen was chosen for both concepts in order to avoid light contamination between measurements and the material sample holder resembles a frame that allows for mounting the material sample outside of the device. The mechanical system has a high stability and the material black anodized aluminum further contributes to the sturdiness of the construction. A physical prototype was created to validate the movement, since the movement of the detector and light source will be similar, only the detector movement was prototyped. The prototype showed that the movement of the detector worked in the desired way, hence the construction of the movement is approved. The scope was delimited in consensus with the project members and supervisors due to the time frame, hence there is future work on the device that should be accounted for. In conclusion, the purpose of the project was fulfilled after delimiting the goals and a conceptual solution was created that fulfilled the requirements of the project. / Optiska mätinstrument används för att mäta ljusreflektion och ljusspridning från material, för att erhålla data om materialets yt- och bulkegenskaper. Mätdata används ofta i forsknings- och utvecklingsprojekt där materialkrav är viktiga, även för kvalitetskontroll i tillverkningsprocesser, i olika optiska simuleringar och kan användas för fotorealistisk rendering. I detta examensarbete, genomfört på AFRY, kommer ett multifunktionellt team att utveckla en optisk spridningsmätningsenhet som syftar till att samla in data mer noggrant. Denna avhandling kommer att fokusera på den mekaniska designen av enheten som består av stabiliteten och rörelsen av komponenterna, mätmiljön och materialval med fokus på prestanda och hållbarhet. Den optiska modellen som kommer att ligga till grund för utvecklingen kommer att vara en gonioreflektometer bestående av ett materialprov, provhållare, ljuskälla, detektor och en miljö där mätningarna genomförs. Några av de fysiska, kognitiva och emotionella behoven hos den avsedda användaren är effektiv användning, låg risk för felanvändning, pålitlighet och hög precision. En noggrann kravspecifikation gjordes som en ram för konceptgenereringen. Det valda konceptet möjliggör rörelse av de optiska komponenterna med ett vinkelsteg som tillåter den önskade optiska spridningsmätningen. Den valda stegmotorn och utväxlingen ger flexibilitet i rörelsen, detta bidrar till att det är enkelt för användaren att ändra vinkelstegen för de optiska komponenterna, vilket tillåter både fina och grova mätningar. En avskiljningsskärm valdes för att undvika ljuskontaminering mellan mätningarna och materialprovhållaren liknar en ram där materialprovet monteras utanför enheten. Det mekaniska systemet har en hög stabilitet och materialet svart anodiserad aluminium bidrar till konstruktionens robusthet. En fysisk prototyp skapades för att validera rörelsen, eftersom rörelsen av detektorn och ljuskällan kommer att vara liknande, återskapades endast detektorns rörelse. Prototypen visade att detektorns rörelse fungerade på önskat sätt, därmed godkänns konstruktionen av rörelsen. Projektets mål avgränsades i samförstånd med projektmedlemmarna och handledarna på grund av tidsramen, därmed finns det framtida arbete för mätinstrumentet som bör beaktas. Sammanfattningsvis uppfylldes projektets syfte efter att målen avgränsats och en konceptuell lösning skapades som uppfyllde projektets krav.